Automatic lead supplying device for a plotter

Abstract

A swivelling unit 18 is swivellably supported on the machine body of the plotter between the two predetermined positions. A loader shaft 38 is journalled on the swivelling unit 18 which is interlocked with a rotary drive device. When the swivelling unit 18 moves to the predetermined lead supplying position, a lead tank stocker 44, having a number of lead tanks on its circumference and connected to the loader shaft 38, moves interlockingly with the swivelling unit 18 in the condition of holding the predetermined rotary angle. The lead tank 48 moves immediately above the pencil holder 10 of the writing instruments stocker 8 by this movement. When the opener 76 is driven to this position and the shutter mechanism of the lead tank 48 opens, a piece of the writing lead drops from the lead tank 48 and the writing lead is supplied to the empty pencil holder 12 which is retained by the writing instruments stocker 8. Since the lead tank stocker 46 is rotatable relative to the swivelling unit 18, the lead tank 48, storing the desired kind of writing lead, can be rotated to the lead supplying position from the number of lead tanks 48. Accordingly, the desired lead tank 48 is chosen, and the selected lead tank 48 moves immediately above the desired pencil holder 10 of the writing instruments stocker 8 and the lead is supplied to the pencil holder 10.